Process of preparing red oxid of iron and zinc sulfate.



EVAN S, 01

AIREN np ieation filed May 22, 1908.

EVANS, a subum, residing: at

#1 q one, oi'rou ureen, .viuldleented u n v; and useiieu Oxirl of iron do hereby declare e or, zlful. et

o; my inthe sine as em compound of inurthe utilization of the e from time to st oi sulfuric acid t concentration the zinc l. mrrhonute 1n (l lllulh Wine-n may be too ntsd profitably by anv of no ri m W. lnost or tnese (1t- 021K181 sally, chiefly on P013. ly always present in wnieh iron uses up a large e sold, and occasions fur- 11g into solution, as sul- I? its object a prooe drznvimek, the is oi" advaniining at ohtuin to free from iron resent, or added therein described, valuable material in eour the 13/ invention .l proceed as say, I mid to the mineral,

rtein amount of ferruginit pvriles, row or calcined rnon depending on the of iron present in the orig nal on, or tnilings, and on the nature of to he aimed rd; For example, ii

i ,agrudo residue, consisting ulol' Ferric oxid, i odd :1. larger .1. the

- is intended only to form material l'ozrughmus mutter than if STROUD GREEN, Eiltiinll Specification 0;? Letters in the original nutteriul :md leave ti Serial No. *1 '1.

The materials are thorouu I and inrorpm'uted, and Illi then of sulfurie acid oi uhout lauiuml'. mmeentruted an arid 1 ho vuslel'ul and inellieient, vsliilco; u of this strength I find that 1111 inil' Lure of all the ingredients run, h and that no portion couted with a crust i so as to he protected from acid. The quantity of sui'i'ieient to eonrort in metals present tlnit are in. tizod.

iVhen any appreciable quin lead, tungsten. and other met soluble or dil'l'ieultly soluble prodL w treated with sulfuric acid are presem, it best to leach out all the sole? l iron, zinc, etc., before attemptiz v or culeine. in such muses the leueh liquid containing all the soluble sull'u is empowited to dryness and the suhstuiu-e left on evaporation eulcined or ignued to destroy the sulfates of iron, etc. and itfili'ilml us before. From the residue lei'i' on {he lirst leaching, 'i. (3,, the insoluble sull'nto of lead or other insoluble substances, the lend or other ny oi the ordithou e:\.l

liud

I sulfates oi' to ignite metul may he olri'uined hy our processes. The mixture i.) (:ined or ignited at :L tempemtuir si lieientlv high to decompose all the suli'sie or sulfates of iron. present; most of the iron l he snomo present as i'errii' sulfate, hut Hie ouloinution or ignilion must ulwu vs he done in u uurrent ol' till, and ample time should he ullm id for the conversion of oil the iron into the lerrio state, and so that all the sulfur in the iron sullutes and other deoomposuhlv suliutes is driven oil' in [he l'orm ol' suli'ur 'irioxid. The muss is tlienleiu-iwd out 1th wider or very dilute sulluru; ueul so us to ohtuin m solution as zine sull'ute oil the zinc an insoluble residue of for rie oxid. fur irioxid driven oil' during" iugzitu einutionis converted into sulfsrio said or stored as trioxid. by any of the ordiuu'iy methods.

I claim 3 The herein desorihed process of t low grade zinc ore containing iron, fin, o 1%., which consists in incmporotiug t' tin l i with l'erruginous meter-in], nursing the terntls with sullurio iu-id ol' about 50 duoni to convert the iron and zinc. into suite leaching out the sulfates of iron and zinc and separating the solid residue therefrom, tree-t ing the residue to obtain lead, tin etc, celoining the sulfates of zinc and iron to decom- Jose the iron sulfate and drive off the sulfur, ieeching out the zinc sulfate and separating therefrom the iron as ferric oxid.

2. In the herein described process of treating low grade zincore containing iron, the improvement which consists in incorporating therewith a quantity of ferruginous material, mixing the materials with sulfuric acid of about 50 Beum in sufficient quentityto convert all the metals present which are cepeble of being sulfetized into sulfates, calcining the mixture in a current of air to de- 'con1pose all the sulfates of iron present and drive off the sulfur as sulfur trioxid and leaching out the zinc present and separating from the mixture the residue of iron as ferric 20 oxid.

3. The herein described process of treating containing iron, which low grade zinc ores consists in treating the ore with sulfuric acid of about 50 Beum to convert the sulfetiz-I able metals into sulfates, calcining the 1ni2rture to decompose the sulfates of iron present, and drive off the sulfur, leaching out the zinc; present, and separating from the mixture the residue of ferric oxid, substuntielly as de- 30 

